if (first == second) {
        return 0;
      } else if (first == null) {
        return -1;
      } else if (second == null) {
        return 1;
      } else if (first.length() != second.length()) {
        return first.length() - second.length();
      } else {
        return first.compareTo(second);
      }
    }
  }

  /** Decreasing integer values. A {@code null} comes before any non-null value. */

  int count;

  @Param({"1", "10"})
  int length;

  private String originalString;

  @BeforeExperiment
  void setUp() {
    originalString = Strings.repeat("x", length);
  }

  @Benchmark
  void oldRepeat(long reps) {
    for (int i = 0; i < reps; i++) {
      String x = oldRepeat(originalString, count);
      if (x.length() != (originalString.length() * count)) {

   */
  public static char[] concat(char[]... arrays) {
    int length = 0;
    for (char[] array : arrays) {
      length += array.length;
    }
    char[] result = new char[length];
    int pos = 0;
    for (char[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

  /**

      String[] suffix = {"f", "g"};
      String[] all = new String[elements.length + suffix.length];
      System.arraycopy(elements, 0, all, 0, elements.length);
      System.arraycopy(suffix, 0, all, elements.length, suffix.length);
      return ImmutableList.copyOf(all).subList(0, elements.length);
    }
  }

  public static class ImmutableListTailSubListGenerator extends TestStringListGenerator {

   */
  public static double[] concat(double[]... arrays) {
    int length = 0;
    for (double[] array : arrays) {
      length += array.length;
    }
    double[] result = new double[length];
    int pos = 0;
    for (double[] array : arrays) {
      System.arraycopy(array, 0, result, pos, array.length);
      pos += array.length;
    }
    return result;
  }

      return asList(all).subList(2, elements.length + 2);
    }
  }

  private static Float[] concat(Float[] left, Float[] right) {
    Float[] result = new Float[left.length + right.length];
    System.arraycopy(left, 0, result, 0, left.length);
    System.arraycopy(right, 0, result, left.length, right.length);
    return result;
  }

    checkNotNull(array);
    checkPositionIndexes(fromIndex, toIndex, array.length);
    if (array.length <= 1) {
      return;
    }

    int length = toIndex - fromIndex;
    // Obtain m = (-distance mod length), a non-negative value less than "length". This is how many
    // places left to rotate.
    int m = -distance % length;
    m = (m < 0) ? m + length : m;

    // Non-null array of zero length.
    assertEquals(0, fem.getReplacementArray().length);
  }

  public void testMapLength() {
    Map<Character, String> map =
        ImmutableMap.of(
            'a', "first",
            'z', "last");
    ArrayBasedEscaperMap fem = ArrayBasedEscaperMap.create(map);
    // Array length is highest character value + 1

    checkArgument(
        string.length() >= 2, "input string (%s) must have at least 2 characters", string);
    checkArgument(
        string.length() % 2 == 0,
        "input string (%s) must have an even number of characters",
        string);

    byte[] bytes = new byte[string.length() / 2];
    for (int i = 0; i < string.length(); i += 2) {
      int ch1 = decode(string.charAt(i)) << 4;

  public final Entry<String, String>[] createArray(int length) {
    return (Entry<String, String>[]) new Entry<?, ?>[length];
  }

  @Override
  public final String[] createKeyArray(int length) {
    return new String[length];
  }

  @Override
  public final String[] createValueArray(int length) {
    return new String[length];
  }

  /** Returns the original element list, unchanged. */
  @Override